Just as siegeworks must be tailored to the stronghold under siege, so, too, must your strikes be fitted to your opponent.  The military strategist Turpin de Crisse wrote:  “One must know the genius, character, and talents of the enemy general; it is on this knowledge that one can develop plans.”

Study the Opponent before Fighting

Caesar would always try to engage the enemy commander in lengthy negotiations, not only so that he might avoid battle, but also to give him a chance to study the commander should he not be able to.  The moment France seemed likely to go to war with another European state, Napoleon would ask his librarian to bring him a great many books on that state, on its history, geography, political life, and leaders.

The opponents of Caesar, Richelieu, Napoleon, Talleyrand, and Gates misunderstood them, and in misunderstanding, lost.

In bickering over consulships and praetorships before the battle of Pharsalus, the optimates, said Plutarch, were “behaving as though their adversary was Tigranes the Armenian or some king of the Nabataeans, when in fact it was Caesar -- Caesar and that army of his with which he had stormed 1,000 cities and subdued more than 300 nations…”

Never, ever suppose that a particular rival cannot hurt you:  history is littered with people whose dismissal of an opponent was soon followed by their succumbing to that opponent.

In the early 1990s, WordPerfect refused to develop a version of its software for Windows 3.0, simply because its market share was so much greater than that of Microsoft Word.  Windows 3.0 was wildly successful, and Word soon surpassed WordPerfect in popularity.  Microsoft has spent billions of dollars countering threats that later turned out to be of little consequence.

Do not assume that your opponent is like you.  As Pharnaces crossed the valley between them, Caesar assumed he would not be so imprudent as to attack the Caesarians upon their steep hill (because Caesar himself would not do such a thing).  When Pharnaces did attack, the Caesarians were so taken by surprise that they very nearly lost.

Early in his career, Napoleon would sometimes make the mistake of assuming his opponent would do what he would do in such a situation; since the opponent was not a military genius, however, he would always do something quite different.

Ask certain questions about your opponent.  Where are his vital points?  How resolute is he?  How willing is he to fight, and to continue fighting?  How will he react to each strike you contemplate?  If you miscalculate here, all may be lost.

Napoleon assumed that once he took Moscow, Tsar Alexander would sue for peace; Alexander did not.

Continue to Study the Opponent while Fighting

In Gaul, Caesar would continually interrogate prisoners, and have his cavalry do reconnaissance, to learn the whereabouts and strategy of his opponents.

Which vital points does your opponent leave undefended?  Have new ones come into being, or been exposed, through his reaction to your strikes, or his striking in turn?  What is his true state?

It is quite natural to see our own wounds and not the opponent’s, to see our own state and not the other’s; but the opponent’s may be far worse than our own.  Napoleon said:  “In war you see your own troubles; those of the enemy you cannot see.”

If you gain a victory or suffer a defeat, consider — rationally rather than emotionally — why you did so.

Do not think yourself victorious; be certain of it.  The Roman dramatist Ennius said:  “The victor is not victorious if the vanquished does not consider himself so.”  Suetonius said of Caesar:  “It was his rule never to let enemy troops rally when he had routed them, and always therefore to assault their camp at once.”